The present invention relates to an apparatus for positioning a ring rail of a textile machine and, more particularly, to an apparatus for positioning aligned, elongate segments of a ring tail relative to vertically movable ring rail supports.
In certain types of textile machines, such as ring spinning and twisting machines, yarn is guided onto a spindle by a traveler which travels around a ring. The rings associated with several adjacent spindles are mounted in a ring rail segment and the segments of an entire row of spindles are aligned with one another to form the ring rail for the row of spindles. In one known arrangement, the adjacent end portions of each adjacent pair of ring rail segments are commonly supported by a support and each support is movably mounted on a vertical guidepost for guided reciprocating vertical motion, whereby a guiding motion is imparted to the spinning operation.
To insure satisfactory travel of the yarn from the traveler onto the spindle, it is especially important that each ring be relatively precisely coaxially aligned with its associated spindle and this precise coaxial arrangement also minimizes the occurrence of yarn breaks. Accordingly, after repair or maintenance of the spinning machine, it is important to again align the rings with their associated spindles. However, a competing consideration is that the ring rails be easily removable and replaceable to facilitate a rapid and efficient maintenance of the spinning machine and this makes it difficult upon replacing the ring rail on to the spinning machine, to again achieve the precise coaxial alignment of the rings in their associated spindles.
In the case of spinning machines having long rows of spindles, it is especially difficult to position the ring rail segments. If the segments are abutted end to end, the ring rail may gain in length due to an increase in temperature, which causes the segments to expand. However, since the segments typically are not coupled to one another, they will not correspondingly return to their original unexpanded positions once the temperature decreases with the result that certain of the rings will no longer be coaxially aligned with their associated spindles.
It has been proposed in German Patentschrift No. 710 608 to precisely longitudinally guide the ring rail segments--that is, to position the segments transverse to the longitudinal axis of the ring rail. Additionally, German Patentschrift No. 809 159 proposes an arrangement of ring rail supports and posts for supporting the ends of the ring rail segments. However, proper alignment of the ring rail segments is difficult to achieve with the arrangement and the arrangement does not insure that the ring rail segments will remain reliably secure in their proper aligned position during the spinning operation, as is necessary to achieve the goal of error-free feed of the yarn during the spinning operation.
It has also been proposed in German Offenlegungsschrift No. 26 32 409 to provide the ends of the ring rail segments with projections and recesses which cooperate with one another in dovetail fashion. However, this arrangement requires additional components in the end portions of the ring rail segments, such as an attachment piece, and this tends to make this arrangement relatively expensive.
In German Patentschrift No. 27 55 590, an arrangement is proposed for providing the ends of the ring rail segments with compatibly configured bores and pegs.